package com.eshop.utils;

import org.mybatis.generator.api.CommentGenerator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.*;
import org.mybatis.generator.api.dom.xml.Attribute;
import org.mybatis.generator.api.dom.xml.TextElement;
import org.mybatis.generator.api.dom.xml.XmlElement;

import java.util.List;

/**
 * MyBatis分页插件
 * @author float.lu
 */
public class PaginationPlugin extends PluginAdapter{
    public PaginationPlugin() {
        super();
    }

    @Override
    public boolean modelExampleClassGenerated(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
        addLimit(topLevelClass, introspectedTable, "limitStart");
        addLimit(topLevelClass, introspectedTable, "limitEnd");
        return super.modelExampleClassGenerated(topLevelClass, introspectedTable);
    }

    @Override
    public boolean sqlMapSelectByExampleWithBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
        XmlElement isNotNullElement = new XmlElement("if");
        isNotNullElement.addAttribute(new Attribute("test", "limitStart != null and limitStart >= 0"));
        isNotNullElement.addElement(new TextElement("limit #{limitStart}, #{limitEnd}"));
        element.addElement(isNotNullElement);
        return super.sqlMapSelectByExampleWithBLOBsElementGenerated(element, introspectedTable);
    }
    @Override
    public boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {
        XmlElement isNotNullElement = new XmlElement("if");
        isNotNullElement.addAttribute(new Attribute("test", "limitStart != null and limitStart >= 0"));
        isNotNullElement.addElement(new TextElement("limit #{limitStart}, #{limitEnd}"));
        element.addElement(isNotNullElement);
        return super.sqlMapSelectByExampleWithoutBLOBsElementGenerated(element, introspectedTable);
    }

    @Override
    public boolean validate(List<String> warnings) {
        return true;
    }
    private void addLimit(TopLevelClass topLevelClass, IntrospectedTable introspectedTable,
                          String name){
        CommentGenerator commentGenerator = context.getCommentGenerator();
        Field field = new Field();
        field.setVisibility(JavaVisibility.PROTECTED);
        field.setType(PrimitiveTypeWrapper.getIntegerInstance());
        field.setName(name);
        commentGenerator.addFieldComment(field, introspectedTable);
        topLevelClass.addField(field);
        char c = name.charAt(0);
        String cname = Character.toUpperCase(c) + name.substring(1);
        Method method = new Method();
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setName("set" + cname);
        method.addParameter(new Parameter(PrimitiveTypeWrapper.getIntegerInstance(),name));
        method.addBodyLine("this." + name + "=" + name + ";");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);
        method = new Method();
        method.setReturnType(PrimitiveTypeWrapper.getIntegerInstance());
        method.setVisibility(JavaVisibility.PUBLIC);
        method.setName("get" + cname);
        method.addBodyLine("return " + name + ";");
        commentGenerator.addGeneralMethodComment(method, introspectedTable);
        topLevelClass.addMethod(method);

    }
}
